8 ohm speaker

It’s been a good long while since I’ve really dissected a bit of electronics. But I finally got another chance after uncovering an old broken CD/radio/cassette player in the basement! After some tests, I determined that the CD player part of it didn’t work. Since no one uses archaic cassette tapes anymore, and a radio that weighs ten pounds is pretty impractical, I naturally snapped it up to tear it apart. 🙂

The boombox before dissection; note that it’s quite dusty. It was manufactured in 1997 so it was about 20 years old.

Disassembling it was pretty trivial. There was only a few screws which held the casing together, and each internal part also held in place with screws. The most challenging part was removing the large speakers. Each was both glued and screwed, so it took a little extra prying to get them off.

The boombox can be powered from both batteries and the house current, so there’s both a transformer and a large compartment to hold eight D cells. There’s one large PCB that combines the circuits for the CD player, cassette player, and radio player, with a few offshoot PCBs to connect the controls.

Receiving the throw-aways from my sister’s toy phone collection for use in my electrical endeavors, I opened up an old Disney store Toy Story fake cell phone to see what I would find. Basically it has 17 buttons, which create assorted noises and blink LEDs on the ‘screen’ and in the antenna. Or at least it used to, because the batteries are long dead.

Taking apart the back first near the batteries, revealed the capacitive printed circuit board for the rubber buttons. On the back side of it, there’s a couple 5% tolerance resistors. Under that, there’s an 8Ω speaker commonly found in many electronics, and you can also see the coin cell holders and the LED connections. The date on the PCB said it was made in June 2003. Other than the screws holding the toy phone together from the outside, the plastic snaps together and keeps the LEDs and PCB in place.

Being a throw-away item, I was able to obtain a few parts for my own use. The resistors are unusable, because the leads are to short, and I have not yet obtained a soldering iron. I always keep all screws from electronics, because I know they’ll come in handy someday.